Magnum breather
 

The M20 in my 2072 has been getting oil on the base the air filter sits on. I researched the archives and found where this was most likely a breather problem. I ordered everything to rebuild the breather. Kohler has obsoleted the umbrella valve and has replaced it with a breather with a reed-valve set-up. I had all the parts on hand before we tore it down. It turns out one gasket and the filter mesh were missing and the umbrella valve was broke. Thanks to whomever it was that suggested this fix.!

Thats why they went to the reed type.